The death of German sailor Stefan Rami has prompted sudden interest in the remote Polynesian island of Nuku Hiva. Prompted by the past cannibalistic traditions of Melanesia and Polynesia, authorities suspect that Rami's local guide, Henri Haiti, not only murdered him, but ate him before burning his body.

Historically, visitors to cannibal tribes often seem to have been remarkably safe, and indeed well treated. Like the mafia, such people usually only killed their own. In the late 16th century, for example, the French writer André Thevet observed Brazilian cannibalism personally, and returned home unscathed. Thevet witnessed both the violent, aggressive cannibalism of warfare, and what is now known as consensual or funerary cannibalism. The Tapuia people, he noted, "ate their own dead relatives to spare them the indignity of rotting in the earth". Around the same time another Frenchman, Jean de Léry, lived with the Tupinamba in Brazil. Yet despite their reputation as some of the most violent cannibals then known, Léry too lived to tell his traveller's tales.

Perhaps strangest of all, however, is the tale of Joseph Kabris, a French sailor who came to live amongst a cannibal tribe on Nuku Hiva from 1796-1804. Jennifer Terrell tells us how, after some initial fears about being eaten, Kabris in fact took to his new life with such a passion that he actually "went native". He was tattooed in tribal fashion, married two different wives, and fought in battle with his new hosts. In time he was supposed to have forgotten the French language, and even his own name. Kabris claimed that: "apart from times of famine or war these islanders are very gentle. Strangers are treated with great respect and can travel through the land... with complete safety."

Admittedly, war and famine on Nuku Hiva were another matter. The adopted soldier Kabris told of how, "after the battle the prisoners are eaten. The eyes, brain and cheeks are regarded as delicacies"; while the scholar George von Langsdorff writes that "the skulls [are] split open, the brains and blood drunk, then scraped clean", before the "jaw is fixed on fibres and carried round as a symbol of valour". Kabris also spoke of how, during famines caused by drought, the islanders would "fight among themselves at the least disagreement, and cut throats to provide food".

This desperate famine cannibalism was known to occur, he added, even within families. The more recent claim that in Melanesia the Korowai of Papua New Guinea still eat human brains warm, matches the details above. Not only are the brains "drunk" (ie they must have been relatively soft still) but the occasional famine cannibalism of the tribe implies that islanders may have developed a taste for human flesh that went beyond questions of culture or religion.

In Kabris's time the islanders do not appear to have practised funerary cannibalism. But, as with the Tapuia, this internal, consensual cannibalism has been far more common than much western travel-writing might suggest. While the Korowai are surprisingly late cannibals, it was as recently as the 1970s that the Guiaca people of the upper Orinoco were still cremating bodies, grinding the half-burned bones, and mixing them into plantain soup to be drunk. Around the same time, we hear of the South American Yanomami that, "when a child dies they consume it so thoroughly, even pulverising the bones and drinking them down in plantain soup, that there is nothing left".

For those involved, these funerals were intensely pious, essentially religious rituals. Nowhere was this more so than among the Wari' of Brazil. Living with the tribe in the 1980s, Beth Conklin heard of the solemn ceremonies in which the Wari' had eaten their dead until, in the 1960s, they were forcibly stopped by government missionaries. Such rites were so thoroughly internal that the Wari' and similar tribes would almost certainly have been repelled by the idea of eating an outsider.

It's also the case that violent cannibalism has occurred sporadically in the "civilised" world. There were many instances in the 1960s during China's cultural revolution; and at least several between Protestants and Catholics during the wars of religion. In Hungary in 1514, after crushing a peasant uprising, nobles roasted alive the rebel leader, and left his deliberately starved followers to eat him.

But perhaps the most memorable tale is one recorded by Frank Lestringant. In 1562 well-meaning missionaries brought a small party of Tupinamba tribesmen to France. Were they awed and impressed? Not exactly … Rather, the Brazilians were "taken aback by the juxtaposition of rich and poor, and wondered how the latter 'could endure such injustice without taking the others by the throat and setting fire to their houses"'.

What would they think of Cameron's Britain?

• This piece was amended on 26 October 2011 to reflect the fact the Korowai are from Papua New Guinea, not Nuku Hiva